Apparatus for and method of opening interpositioned folded sheets

ABSTRACT

Apparatus for and method of centrally opening two folded interpositioned sheets which are deposited with their edges parallel to their rear fold facing forwards by a roller conveyor receiving the sheets through a spreading device onto a conveyor serving as transport means for the open sheets, comprising the steps of: spreading the outer sheet portions apart from the inner sheet portions, and maintaining the outer spread sheet portions while concurrently spreading the inner sheet portions.

United States Patent Hepp 51 Mar. 21, 1972 [54] APPARATUS FOR AND METHOD OF 3,176,976 4/1965 l-lepp ..270/54 OPENING INTERPOSITIONED FOLDED 2,966,353 1211960 Gorem 85 E 1,202,80 10 1916 Curry.. ..27 55 SHE TS 3,169,762 2/1965 Parks ..270/55 [72] inventor: Rudolf Hepp, Schmidt-Ott-Strasse 7a, Beriin, 41, Germany FOREIGN PATENTS OR APPLICATIONS 22 Filed; 5 19 9 396,816 8/1933 Great Britain ..270/54 PP' -I 882, 99 Primary ExaminerRobert W. Michell Assistant Examiner-L. R. Oremland [30] Foreign Application Priority Data At'0rney"'Kar| Ross Dec. 23, 1968 Germany ..P 18 17 648.2 [57] ABSTRACT [52] US. Cl I 270/54 270/57 Apparatus for and method of centrally opening two folded in- [51] Int Cl B65h 39/02 terpositioned sheets which are deposited with their edges 58] Fie'ld /54 55 57 parallel to their rear fold facing forwards by a roller conveyor receiving the sheets through a spreading device onto a con- [56] Reerences Cited veyor serving as transport means for the open sheets, comprising the steps of: spreading the outer sheet portions apart from UNITED STATES PATENTS the inner sheet portions, and maintaining the outer spread sheet portions while concurrently spreading the inner sheet 2,390,901 12/1945 Schramm ..270/54 portiorm 2,817,513 12/1957 Bell et al..... ..270/54 1,294,559 2/1919 Sproui ..270/55 4 Claims, 10 Drawing Figures Patented March 21, 1972 3,650,524

2 Sheets-Sheet 1 In ventor= Patented March 21,1972 4 3,650,524

2 Sheets-Sheet 2 Fig. 6

RUDULF HEPP Inventor:

APPARATUS FOR AND METHOD OF OPENING INTERPOSITIONED FOLDED SHEETS folded sheets along their backs, i.e., along the folded edges by 1 means of so-called thread book sewing machines. The sheets are usually printed individually in printing presses and then folded in folding machines to the required size and the required number of pages. The folding methods may differ. A folding machine may process two sheets, positioning one in the other defining an aligned or common crease. Additional sheets may be fixed by gluing to the folded edge of the outer sheets of the two interpositioned sheets. For further processing by a thread book sewing machine, these sheets must be opened in the center along the crease and placed on a transport device such as an inverted V-shape saddle which carries the opened sheets to the thread book sewing machine where they are secured with other sheets by sewing to form the book block.

This central opening of such folded sheets, positioned inside each other, is difficult to achieve by means of known mechanical spreading devices, because both interpositioned sheets must be opened exactly in the center. It is particularly difficult to open such interpositioned sheets in the center if further sheets are fixed by gluing to one side of the outer sheets. The folded sheets are positioned, with their edges parallel to the back fold facing forward through a roller conveyor which embraces the sheets and through a spreader on a conveyor serving to transport them to the thread book sewing machine. Known spreading members of this kind are not capable of producing a perfect central opening of two interpositioned sheets in a reliable manner, because the spreading members of the known construction can always act only on the outer parts of the sheets.

It has already been proposed to accomplish the opening of the inner parts of the sheets in that a spreading tongue, adapted to be pivoted into the path of the sheets is arranged, for spreading the outer sheet portions above the conveyor leading to the thread book sewing machine in order to achieve also the opening of the inner parts of the sheet. However, this arrangement does not work reliably.

SUMMARY OF THE INVENTION The invention has the object of providing a method and a device whereby it is possible to accomplish the reliable opening of two interpositioned sheets in the center without additional transport paths even where additional sheets are mounted on one side of the folding edge of the outer sheet by gluing.

According to the invention, this object is realized by a method characterized in that first the outer parts of the sheet are spread off the inner parts of the sheet and then the inner parts of the sheet are spread apart whilst maintaining the spreading of the outer parts of the sheet. According to another feature of the invention, in the case of additional sheets mounted one-sidedly on the folding edge of the outer sheet by gluing, only the parts of the sheets of the interpositioned sheets opposite the additional sheet or sheets are spread apart.

The device for carrying out the method is characterized in that the spreading device serving for opening the parts of the sheets has two superimposed pairs of gripping members, of which the upper pair consists of gripping members gripping the outer sheetportions and mounted at their free ends on vertically moved arms, and the lower pair consists of known rotation gripping members, wherein the pivoting rhythm of the upper pair is controlled as a function of the speed of the lower pair. According to another feature of the invention, the gripping members are suction elements, known per se and acting on the outside of the associated sheet portion, and arranged outside the roller conveyors, wherein the upper pair of grippers is positioned in the gripping position preferably at a level corresponding substantially to the center of the roller conveyor. In addition, the device is characterized in that one gripping element of the lower pair of gripping elements carries a cam disk serving to control the pivoting movement of the upper pair of gripping elements; one :side of the cam disk has mounted thereon a control lever carrying on one end a toothed segment engaging into a gear mounted coaxially at the pivoting center of the superimposed gripping element of the upper pair of gripping elements and wherein the gripping elements of the upper pair have arms mounted coaxially at the pivoting center and interconnected by a linkage. It is also important that the rotating gripping elements of the lower pair have each an abutting surface adapted to receive the edges of the sheet portions stripped off by the upper pair. Finally, it is also essential that in the case of folded, interpositioned sheets provided one sidedly with additional sheets, the gripping elements of the two pairs of grippers facing the additional sheet are not affected by suction air and that a pivotable guide tongue engaging into the one-sided spreading is arranged above the conveyor serving for the transport of the open sheet.

BRIEF DESCRIPTION OF THE DRAWING The invention will be further described by way of example with reference to the accompanying drawings, in which:

FIG. I shows diagrammatically two interpositioned folded sheets;

FIG. 2 is a representation corresponding to FIG. 1 with a further folded sheet mounted by gluing on one side of the outer folded sheet;

FIG. 3 is a diagrammatical view of the device according to the invention in side elevation;

FIGS. 4 to 8 are front elevations of the device according to FIG. 3 in different operating positions and;

FIGS. 9 and 10 show the device according to FIG. 7 when processing a sheet according to FIG. 2.

DETAILED DESCRIPTION OF THE INVENTION FIG. 1 shows two folded interpositioned sheets 1; FIG. 2 shows also two folded interpositioned sheets 1 wherein a further folded sheet 2 is fixed by gluing to the folding edge on one side ofthe outer folded sheet 1.

As shown in FIGS. 3 and the following FIGS., sheets according to FIGS. 1 and 2 are continuously advanced downwardly with their edges parallel to the folding edge facing forward by driven roller conveyors 3 pressing against the sheet surface. As shown in FIG. 3, the spreading device is arranged to operate near a transverse edge 4 of the :sheet 1, 2.

The device consists of a pair of upper gripping elements 5 constructed as suction elements and a pair of lower rotating suction grippers 6 secured to rotatable, horizontal, parallel shafts. The suction grippers of the present invention may be known convex rubber suction cups which are pressed against a flat surface to evacuate air in the convex cavity and release when air escapes into the cavity. It should be appreciated however that a part communicating with a vacuum pump could also serve to provide suction. The grippers 5 of the upper pair are mounted on arms 7 pivotable at their free ends about horizontal, parallel shafts 8 in the direction of delivery. For the simultaneous and cooperating movement of both suction grippers 5, cranks 9 are secured to shafts 8; the cranks are interconnected by a linkage l0. Spaced from the cranks on the shaft of the left gripper 5 is gear 11 which meshes with a gear segment 12. The segment is mounted on pivotal arm 13 which carries a running roller 14 at its end. The shaft on which left suction gripper 6 is mounted is provided with a cam disk 15 whose control face is engaged by roller 14. The control face of the cam disk 15 includes the radially recessed portion 16 which controls the motion of pivot of arm 13. As shown in FIGS. 4 to 9, the suction grippers 5 of the upper pair are in the gripping position when the roller 14 is located on the recessed part 16 of the cam disk 15. When the roller 14 reaches the,

larger diameter periphery of the cam disc 15, the gripping elements are rotated downwardly.

The suction grippers 6 of the lower pair are mounted on arms 17 secured to the driven rotatable shaft, each equipped with a beveled surface 18 adapted to engage the outer sheet portions spread by grippers 5 to permit the grippers 6 to have access to the internal sheets, illustrated in FIGS. 6 and 7. When the sheet portions of the inner sheet 1 reach the zone of the lower pair of suction grippers 6, they are spread apart, as shown in FIG. 6, while the spreading of the outer sheet portions is maintained by the surfaces 18. In this way, as shown in FIG. 8, the interpositioned folded sheets 1 are deposited after central opening on the inverted V-saddle 19 of the conveyor leading to the thread book sewing machine.

The upper and lower pair of grippers are mounted on a common mounting frame 20. It should be appreciated that the rotation of drive rollers 3 is in timed relation to the driven shafts of arms 17 so that the spreading operation is consistent with the linear movement of the folded sheets.

In FIGS. 9 and the object is to open a sheet according to FIG. 2. In FIG. 9 the additional sheets fixed by gluing, are arranged on the right side, in FIG. 10 on the left side. According to FIG. 9, the two left-hand sheet portions of the interpositioned sheets 1 must be spread while a spreading of the righthand sheet portions cannot be effected in the device. In FIG. 10 the position is reversed. In order to achieve also here a perfect central opening of the two interpositioned sheets, a pivotable tongue 21 is provided which is located immediately above the saddle l9 and ensures by its correct positioning that the unspread sheet portions are so deflected that they position themselves correctly above the saddle 19. Obviously, the tongue 21 must be so arranged that it enters into the path of travel of the sheets 2 in such a manner that it does not prevent them from being deposited on the saddle 19.

The operation of the device according to the invention is as follows. As shown in FIG. 4 the two interpositioned folded sheets 1 are moved in a downward direction by the roller conveyor 3. The upper pair of grippers acts at the level of the center of the roller conveyor 3 and spreads during its downward pivoting movement the outer sheet portions as shown in FIG. 5. According to FIG. 6, the edges of these outer sheet portions are deposited on abutment faces 18 so that during the further downward movement of the roller conveyor 3, the outer sheet portions are held in their spread apart position. As shown in FIG. 6, the suction elements 6 of the lower pair act on the edge zones and the inner sheet portions 1, causing them to be spread apart under rotation whilst the edges of the outer sheet portions 1 are retained in the spread apart position on the surfaces 18, as shown in FIG. 7. The two interpositioned folded sheets, opened in the center in this manner, are then deposited, as shown in FIG. 8 on the saddle 19 of the conveyor leading to the thread book sewing machine so that they can be sewn in this machine along the folding edges.

In FIG. 9 and FIG. 10 only the left-hand, and right-hand suction elements 5, 6 respectively are supplied with suction air so that only the left-hand and right-hand sheet portions of the two interpositioned sheets are spread, whilst the other sheet portions are not spread apart; this is achieved in that the righthand (FIG. 9) or the left-hand (FIG. 10) suction elements 5, 6 are not supplied with suction air. By suitably pivoting the tongue 21, also the unspread sheet portions are deflected by the tongue 21 so that also the sheets of FIG. 2 undergo a reliable central spreading.

What I claim is:

l. A method of centrally opening two folded sheets positioned one within another, comprising the steps of displacing said sheets in a direction perpendicular to the fold with the fold rearmost and free edges of the sheet foremost; gripping outer surfaces of leaves of the outermost sheet and deflecting same outwardly while continuing the advance of said sheets;

subsequently engaginglouter surfaces of the leaves of the inner sheet and deflecting t e same outwardly independently of the leaves of said outer sheets while continuing the displacement of said sheets; and depositing the thus spread sheets upon a saddle, the leaves of said outer sheets being held outwardly and away from the leaves of said inner sheet until said sheets are fully spread.

2. An apparatus for spreading inner and outer interpositioned folded sheets having leaves with free edges remote from the fold, said apparatus comprising means for displacing said sheets in a direction perpendicular to said fold and with said fold rearmost and said edges foremost; first suction means flanking said sheets and engageable with opposite sides of the leaves of the outermost sheet for spreading said leaves of said outermost sheet outwardly during continued advance of said sheets; second suction means disposed downstream of said first suction means and flanking said leaves of said inner sheet but disposed within the spread of the leaves of said outer sheet for engagement with the leaves of said inner sheet to spread the same simultaneously with the spread of said outer sheets during continued advance of said sheets and while maintaining a separation between the leaves of said inner sheet and the leaves of said outer sheet; and an inverted V-saddle in the path of said sheets for receiving the spread sheets, each of said suction means includes a respective suction device engageable with the outer surface of a respective leaf and means operatively connecting said devices for rotatable movement in opposite senses.

3. The apparatus defined in claim 2 wherein said second suction devices include means for maintaining a separation between the inner and outer leaves on a respective side of a fold.

4. The apparatus defined in claim 3 wherein said means for advancing said sheets includes a pair of rollers disposed on opposite sides of said sheets for engaging same ahead of said first suction means. 

1. A method of centrally opening two folded sheets positioned one within another, comprising the steps of displacing said sheets in a direction perpendicular to the fold with the fold rearmost and free edges of the sheet foremost; gripping outer surfaces of leaves of the outermost sheet and deflecting same outwardly while continuing the advance of said sheets; subsequently engaging outer surfaces of the leaves of the inner sheet and deflecting the same outwardly independently of the leaves of said outer sheets while continuing the displacement of said sheets; and depositing the thus spread sheets upon a saddle, the leaves of said outer sheets being held outwardly and away from the leaves of said inner sheet until said sheets are fully spread.
 2. An apparatus for spreading inner and outer interpositioned folded sheets having leaves with free edges remote from the fold, said apparatus comprising means for displacing said sheets in a direction perpendicular to said fold and with said fold rearmost and said edges foremost; first suction means flanking said sheets and engageable with opposite sides of the leaves of the outermost sheet for spreading said leaves of said outermost sheet outwardly during continued advance of said sheets; second suction means disposed downstream of said first suction means and flanking said leaves of said inner sheet but disposed within the spread of the leaves of said outer sheet for engagement with the leaves of said inner sheet to spread the same simultaneously with the spread of said outer sheets during continued advance of said sheets and while maintaining a separation between the leaves of said inner sheet and the leaves of said outer sheet; and an inverted V-saddle in the path of said sheets for receiving the spread sheets, each of said suction means includes a respective suction device engageable with the outer surface of a respective leaf and means operatively connecting said devices for rotatable movement in opposite senses.
 3. The apparatus defined in claim 2 wherein said second suction devices include means for maintaining a separation between the inner and outer leaves on a respective side of a fold.
 4. The apparatus defined in claim 3 wherein said means for advancing said sheets includes a pair of rollers disposed on opposite sides of said sheets for engaging same ahead of said first suction means. 